As components in an Integrated Circuit (IC) continues to increase in density, a spacing between the components is getting smaller and smaller. This causes an increase in parasitic capacitance between the respective components such as a gate electrode and a contact in the IC, and thus deteriorates the performance of the IC. On the other hand, even for devices with low performance requirements, it is also desirable to achieve low power consumption, and thus it is desirable to reduce the capacitance. One way to suppress this increase in the capacitance is to use an air gap between the components, but it may cause problems with mechanical and electrical stability.
Therefore, it is desirable to reduce the capacitance between the components while the spacing between the components continues to decrease.